Perhaps the most obvious theme of this work is the danger of allowing governments to gain totalitarian control over its populace. Totalitarian governments can achieve this by professing to be democratic or socialist, when in reality they are fascist. Orwell cautions the reader to be aware of propaganda. He shows how governments can make statements directly contrast reality, and when repeated enough, those statements can be accepted as fact. By setting the novel in Britain, and having the characters address each other with the communist moniker "Comrade", Orwell alludes that this kind of government can arise from democratic and socialist governments.
Mind Control and Nature of Reality
A second theme concerns the nature of reality. Human perception of reality is a function of the mind. If a person's beliefs are altered, in this case through language and thought control, then that person's understanding of reality can be similarly altered. By describing this dystopian future, Orwell cautions the reader against allowing others to control a person's perceptions. If a person does not control his or her own mind, then that person becomes susceptible to being controlled by propaganda, which allows the spirit of Man to wither and die.
Importance of education
Orwell suggests by the events in the novel that education is vital to controlling one's own mind, thus preventing others from controlling it. By raising one's own awareness and being able to perceive truth, one can defend one's self against mind control. The prime example of this in the novel is the "proles"—an oppressed people who could easily overthrow their masters if not for their own ignorance and general lack of awareness.